“Stem Cells and Asymptomatic Dengue Virus Infection”

Start Date & Time: 
Tuesday, 12 December, 2017 - 15:00
End Date & Time: 
Tuesday, 12 December, 2017 - 16:00

Meeting Room 7C
Level 7
Duke-NUS Medical School
8 College Road, Singapore 169857


Speaker Details: 

Professor Guey-Chuen Perng (Oscar)
Department of Microbiology and Immunology
National Cheng Kung University, Taiwan



Dengue is one of the most important mosquito-borne human viral diseases, threatening to public health globally. Although mosquitoes play important role in the spread of DENV, other routes of transmission, such as mother-to-baby vertical transmission (so called congenital dengue), blood transfusion, stem cells and organ transplantations, have been escalated in recent years, suggesting that DENV may have a capacity of staying in human body for a long time without induction of clinical symptoms. Our local community survey has identified a few asymptomatic subjects with high viral titers circulating in peripheral blood. Previously, we have reported that specific stem cells and progenitor cells in human bone marrow (HBM) can be infected by DENV. Upon further ex vivo investigations, umbilical cord blood (UCB) cells could be efficiently infected by DENV. Interestingly, infectious DENV could be recovered from the stem and megakaryocytic lineage cells isolated from the period in which no infectious virus was detected in supernatants of infected UCB by co-culturing with Vero cells. Humanized mice data demonstrated that DENV could establish persistent and/or latent infection, dependent upon the source of stem cells (HBM or UCB) utilized to transplant and generate the humanized mice. Detail investigations demonstrated that DENV infected and established persistent and/or latent infections in stem and megakaryocytic progenitor cells. These results suggest that DENV infects specific stem and progenitor cells to maintain and circulate within human society. The current finding, if verified in human beings, indicates that DENV can evade human immune system and cohabitate with its host peacefully, and that a new challenge in prevention and controlling measure to mitigate the cycling pattern of DENV outbreak.


Guey Chuen Perng, nick name Oscar, earned his Ph.D. from the Department of Microbiology and Immunology at University of California, Davis, and got his postdoc training at Cedars-Sinai Medical Center (CSMC), an affiliated teaching hospital to University of California, Los Angeles. Oscar was an Assistant Professor at UC Irvine and served as Director of Arbovirology division at AFRIMS, an affiliated research institute to US Military in Bangkok, Thailand. In 2007, Oscar was recruited to the Department of Pathology and Laboratory Medicine as an Associate Professor at Emory University. Currently, Oscar is a Professor at Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

The theme of Oscar’s research is to understand the pathogenic process of disease development during viral infections. The main focus of his research is on the role of stem and progenitor cells in development of mosquito-borne viral diseases as well as the fate of these cells after encountering the virus. Dissecting the dynamic interactions between viruses and a susceptible stem and progenitor cells or host immune factors is the methodological approach to achieve the goal.


Professor Ooi Eng Eong
Programme in Emerging Infectious Diseases

Contact Person: 

Sandie Lim